Lattice oxygen activation enabled by high-valence metal sites for enhanced water oxidation

Ning Zhang; Xiaobin Feng; Dewei Rao; Xi Deng; Lejuan Cai; Bocheng Qiu; Ran Long; Yujie Xiong; Yang Lu; Yang Chai

doi:10.1038/s41467-020-17934-7

Lattice oxygen activation enabled by high-valence metal sites for enhanced water oxidation

Nat Commun. 2020 Aug 13;11(1):4066. doi: 10.1038/s41467-020-17934-7.

Authors

Ning Zhang^#^{1

2}, Xiaobin Feng^#^{3

4}, Dewei Rao^#⁵, Xi Deng⁶, Lejuan Cai^{1

2}, Bocheng Qiu^{1

2}, Ran Long⁶, Yujie Xiong⁶, Yang Lu^{7

8}, Yang Chai^{9

10}

Affiliations

¹ Department of Applied Physics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, P. R. China.
² The Hong Kong Polytechnic University Shenzhen Research Institute, 518057, Shenzhen, P. R. China.
³ Department of Mechanical Engineering, City University of Hong Kong, Kowloon, Hong Kong, P. R. China.
⁴ Nano-Manufacturing Laboratory (NML), Shenzhen Research Institute of City University of Hong Kong, 518057, Shenzhen, P. R. China.
⁵ School of Materials Science and Engineering, Jiangsu University, 212013, Zhenjiang, Jiangsu, P. R. China.
⁶ Hefei National Laboratory for Physical Sciences at the Microscale, iChEM (Collaborative Innovation Center of Chemistry for Energy Materials), School of Chemistry and Materials Science, National Synchrotron Radiation Laboratory, University of Science and Technology of China, 230026, Hefei, Anhui, P. R. China.
⁷ Department of Mechanical Engineering, City University of Hong Kong, Kowloon, Hong Kong, P. R. China. yanglu@cityu.edu.hk.
⁸ Nano-Manufacturing Laboratory (NML), Shenzhen Research Institute of City University of Hong Kong, 518057, Shenzhen, P. R. China. yanglu@cityu.edu.hk.
⁹ Department of Applied Physics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, P. R. China. ychai@polyu.edu.hk.
¹⁰ The Hong Kong Polytechnic University Shenzhen Research Institute, 518057, Shenzhen, P. R. China. ychai@polyu.edu.hk.

^# Contributed equally.

Abstract

Anodic oxygen evolution reaction (OER) is recognized as kinetic bottleneck in water electrolysis. Transition metal sites with high valence states can accelerate the reaction kinetics to offer highly intrinsic activity, but suffer from thermodynamic formation barrier. Here, we show subtle engineering of highly oxidized Ni⁴⁺ species in surface reconstructed (oxy)hydroxides on multicomponent FeCoCrNi alloy film through interatomically electronic interplay. Our spectroscopic investigations with theoretical studies uncover that Fe component enables the formation of Ni⁴⁺ species, which is energetically favored by the multistep evolution of Ni²⁺→Ni³⁺→Ni⁴⁺. The dynamically constructed Ni⁴⁺ species drives holes into oxygen ligands to facilitate intramolecular oxygen coupling, triggering lattice oxygen activation to form Fe-Ni dual-sites as ultimate catalytic center with highly intrinsic activity. As a result, the surface reconstructed FeCoCrNi OER catalyst delivers outstanding mass activity and turnover frequency of 3601 A g_metal^-1 and 0.483 s^-1 at an overpotential of 300 mV in alkaline electrolyte, respectively.